Oil supply indicating mechanism for internal combustion engines



an, 7, 1941. w. M. ROBISON 2,227,555 OIL SUPPLY INDICATING MECHANISM FORINTERNAL COMBUSTION ENGINES Filed May 29, 1939 fzzzdzrrllrlrll v r[III/ll 3 W1) Mm mmM Baa/(Sm,

Patented Jan. 7, 1941 UNITED STATES PATENT OFFICE ML iilUPPLY INDICATINGMECHANISM FOR INTERNAL COMBUSTION ENGINES 6 Claims.

The present invention has for its primary object the provision of amanually operated mechanism for electrically suspendingthe operation ofthe ignition system of an internal combus' tion engine, when the oilsupply therefor has be come diminished to a point where serious andcostly damage might. result to the motor, unless the supply of oilisreplenished.

In carrying out the invention I comprehend a mechanism for the abovementioned purpose which is maintained normally inactive by the usualsuction created in the oil supply system for the engine, and whichmechanism is rendered operable when the suction ceases to exist incidentto the reduction of the oil supply for the engine.

In accordance with the instant invention, the mechanism above referredto is included in an auxiliary electrical circuit with the ignitionsystern for the engine. and influenced by the usual 20 suction createdin the oil supply system therefor, so that said mechanism is normallymaintained inactive until the suction ceases to exist incident to theoil supply becoming substantially exhausted, whereupon the mechanismfunctions to cut out the ignition system and consequently stop theengine.

The invention also comprehends the use of a manually operated means forcontrolling the operation of the mechanism above mentioned when the oilsupply for the engine has become substantially exhaustedso that theengine may be started under such condition, and permitted to operate ata comparatively low speed until an opportunity is had to replenish theoil supply.

.The nature and advantages of the invention will be better understoodwhen the following de ail description is read in connection with theaccompanying drawing, the invention residing in the construction,combination and arrangement of parts as claimed.

In the drawing forming part of this application, like numerals ofreference indicate similar parts in the several views and wherein:

Figure 1' is a vertical sectional view through the suction controlleddevice.

Figure 2 is a diagrammatic view partly in section.

Figure 3 is a similar view of a slightly modified form of the invention.7 y

The instant invention is primarily intended for use as an attachment formotor vehicles, but its general application to internal combustion engines is contemplated by the claims.

The mechanism constituting the subject mat- 55 ter of the presentinvention embodies an air tight casing Ill which may vary in size andconstruction without departing from the spirit of the invention. Thecasing is preferably in the nature of a small cylinder whichcommunicates with the suction side of a conventional oil pump "(not 5shown) in the oil supply system for an internal combustion engine. Thecasing II] is preferably provided with a threaded nipple ll with whichthe suction line H! is coupled in any suitable' manner as at l3. Mountedwithin the casing 10 in any desired manner is a partition ll ofinsulated material which supports electrical contacts J5. These contactsmay be of any'suit able construction and supported in any manner by thepartition I 4, with the contacts projecting beneath the latter as shown.The partition is also provided with a central opening through whichslides a piston rod [6 having an annular groove to accommodate thecontact plate or disk ll, thus affording the latter sufiicient freedomof movement to insure effective contact or engagement thereof with thecontacts l5 under certain conditions. The piston rod I6 is yieldablymounted within the casing l0, being influenced in a downward directionby the usual suction created in the oil supply system, in a manner to bepresently described, while the piston rod is moved in an upwarddirection by a suitable spring. Disposed within the casing II] is andiaphragm l8 connected with the piston rod l6. This diaphragm may bemounted in the casing in any suitable manner, but the casing I0 ispreferably provided with an internal flange Ill, between which and thelower portion 20 of the casing the diaphragm is clamped. The adjacentendof the piston rod l6 passes through the diaphragm l8 and is securedthereto by washers 2| arranged above and below the diaphragm asillustrated in Figure 1. Interposed between the lower end of the pistonrod and the bottom of the casing I0 is a coil spring 22 of properstrength and tension to move the piston rod l6 upwardly when the suctionbeneath the diaphragm ceases to exist. which of course occurs when theoil supply for the engine has become substantially exhaus'ted. Asillustrated, one end of the spring is seated in a suitable pocket formedin the lower end of the casing and insulated therefrom.

Upon inspection of the drawing it will be noted to that the device abovedescribed is included in a normally open auxiliary circuit with theignition system for the engine and controlled by a suitable switch.Obviously, the contacts l5 are connected with binding posts 23, one ofwhich is as ignition system. The other binding post is connected by thewire 26 to a manually operated switch, the construction and purpose ofwhich will be presently described.

The manually controlled switch may of course vary in construction andlocation without departing from the inventive idea, and that is hereinshown and described is merely illustrative of preferred embodiments ofthe invention.

In the diagrammatic view Fig. 2, I have shown a switch of the pushbutton type which is adapted to be mounted on a suitable support, ,suchas for instance the dash board 21 o a motor operated vehicle. The switchembodi s a pair of spaced stationary contacts 28 between which operatesthe movable contact carried by the stem of the push button 29. These cntactsare disposed within a suitable shell or casing attached to thesupport 21 as illustrated, the wire 26 of the auxiliary circuit beingconnected to one of the stationary contacts 28, while the other of theseStationary contacts N is grounded. A spring 30 surrounds the stem of thepush button, being interposed between the push button proper and thesupport 21. This spring normally maintains the switch closed asillustrated.

As above stated, the invention is primarily intended or use on a motoroperated vehicle, and in practice, when the engine-contains a suincientquantity oi oil, a suction is created in the casing l0 beneath thediaphragm through-thesuction line or pipe I2. Under these circumstances,the diaphragm i 8 is lowered by said vaccum against the tension of thespring 22, thereby holding the contact plate or disk I! spaced from thecontacts l5, but with the switch above described closed. Consequently,the auxiliary circuit is rendered inoperative, so that the engine may beoperated normally as long as it contains a suflicient quantity of oil.However, should the supply of oil become substantially exhausted, orreach a dangerously low level, the suction in the lower end of thecasing l0 ceases to exist, whereupon the spring 22 moves the piston rodupwardly bringing the contact plate or disk ll into engagement with thecontact I! thus closing the auxiliary circuit, including the coil 25,which of course electrically cuts out the ignition system, stopping theengine. Manifestly, when this occurs, the driver oi the vehicle is thusacquainted with the tact that the supply oimotor oil must bereplenished.

However, the engine can'again be started un- I der such conditions bymerely opening the push button switch, which is preferably located on 1the dash board of the vehicle and within convenient reach of the driver.Again, ii'it is found necessary to drive the-vehicle to a servicestation for oil, the push button switch can be held open by the driver,and the vehicle driven at a comparatively low speed a reasonabledistance without serious damage being. done to the engine. Obviously,when the push button switch is opened, the auxiliary circuit is renderedinactive.

In Figure 3 I have illustrated a slightly modifled form of theinvention, in so far as the manually controlled switch is concerned.Otherwise, the invention is just the same as hereinabove described. Inthis embodiment of the invention, the manually controlled switchincludes a block 3| adapted to be attached to some convenient part ofthe vehicle, and supports a contact finger 32 arranged in the path ofmovement of a conconnected by the wire 24 to the coil of said tactcollar 33 adjustably mounted upon the throt tle operating rod 34. Thewire 24 of the auxiliary circuit electrically connects the suctioninfluenced device with the ignition coil 25, while the wire 26 connectsthe contact finger 32 with one 01' the stationary contacts I5 of thedevice as shown. By virtue of this contruction, when the oil supply inthe engine becomes substantially exhausted, the piston rod I6 iselevated by the spring 22 causing the contact plate or disk I! to engagethe contacts i5 of the device. However, the auxiliary circuit is notcompleted until the manually operated switch is closed. Maniiestly, whenthe contact collar 33 is brought into engagement with the contact finger32, the auxiliary circuit is completed, thereby rendering the ignitionsystem inactive causing the engine to stop. As above stated, the contactcollar 33 is susceptible of longitudinal adjustment on the throttleoperating rod 34 so that it can be set to regulate or vary thepredetermined maximum speed of the engine at which the ignition systemis rendered inactive, and at the same time permit normal operation ofthe ignition system at a comparatively low engine speed, which will notdo serious damage to the engine, until an oppor- I tunity is affordedwithin a reasonable time to replenish the supply of engine 011.

While it is believed that from the foregoing description the nature andadvantages of the invention will be readily apparent, I desire to haveit understood that I do not limit myself to what is herein shown ordescribed, and that such changes may be resorted to when desired as fallwithin the scope of what is claimed.

What is claimed is:

1. The combination with an internal combustion engine and an ignitionsystem therefor, of

. cutting out said system when the engine oil supply becomessubstantially exhausted, saidmech anism including a normally openauxiliary circuit connected with-said ignition system, a manuallyoperable switch for closing said auxiliary circuit at a predeterminedaximum speed of the engine, and means whereby said switch can beadjusted for varying the predetermined maximum speed of the engine atwhich the operation of said ignition system is suspended.

3. The combination with an internal combustion engine, and an ignitionsystem therefor, of a normally open auxiliary circuit, a suctioncontrolled device included in said circuit for initially connecting thecircuit with the ignition system when the engne oil supply becomessubstantially exhausted, and a manually operable switch for closing saidauxiliary circuit and thereby electrically cutting out said ignitionsystem at a predetermined speed of the engine.

4. The combination with an internalcombustion engine, and an ignitionsystem therefor, of a normally open auxiliary circuit, a suctioncontrolled device included in said auxiliary circuit for partiallyconnecting the circuit with the igni-- tion system when the engine oilsupply becomes .substantially exhausted, a manually operable switch forcompleting said auxiliary circuit and thereby electrically cutting outsaid ignition system at a predetermined speed of the engine, and meanswhereby said switch can be adjusted for varying the predeterminedmaximum speed of the engine at which the operation of the ignitionsystem is suspended.

5. The combination with an internal combustion engine, and an ignitionsystem therefor, of a normally open auxiliary circuit, a suctioncontrolled device included in said auxiliary circuit, and embodying anair tight casing, a yieldably mounted pistonrod operating in said casingto partially provide an electrical connection between the casing andsaid ignition system, when the oil supply for the engine has becomesubstantially exhausted, said piston rod being normally maintained bysuction in an inactive position, and an adjustable manually operableswitch for completing said auxiliary circuit at a selected predeterminedspeed of the engine, and thereby electrically cut out said ignitionsystem.

6. The combination with an internal combus tion engine having a throttleoperating rod, a suction line, and an ignition system, of a normallyopen auxiliary circuit electrically connected with said ignition system,a suction controlled device included in said auxiliary circuit forpartially closing thelatter when the oil supply for the engine hasbecome substantially exhausted, and an adjustable switch controlled bythe movement of said throttle operating rod for completing saidauxiliary circuit and simultaneously cutting out the ignition system ata predetermined speed of the engine.

WILLIAM M. ROBISON.

